soil

For a while, this topic was coming up every few months. Here’s an example from an e-mail inquiry. I paraphrase the words here, but keep the punctuation intact, and I omit course, company, and superintendent names:

In July 2015 I led a seminar entitled “A discussion mostly about the principles of turfgrass nutrition, with a focus on soil nutrient analyses and their use in modern turf management.

At first appearance, the demand-driven fertilization of STERF seems almost the same as the growth potential (GP) and MLSN approach. If you are not familiar with this approach from STERF, you can download their Precision Fertilisation – from theory to practice handbook, written by Tom Ericsson, Karin Blombäck and Agnar Kvalbein.

After a talk at a seminar about estimating nutrient use, there were a couple questions that I answered quickly. I take the opportunity to elaborate on my answers here. 1. When looking at soil test results, how to consider the availability of nutrients?

On sand putting greens, it is. The problem caused by sodium is a reduction in the downward movement of water in soils. This is caused by the deflocculation of clay in the soil.

In a conversation on Twitter, Carmen Magro and I showed a fundamental difference in thinking about turf nutrition. My approach, which I explain in Everything you need to know about turfgrass nutrition in 1 lecture, is summarised by this statement:

There is a fine article by Karcher and Richardson in GCM about the effect of wetting agents. In the article, they point out something important: It is often stated that some wetting agents move water rapidly through the root zone while other products retain considerable moisture near the surface, but the data to substantiate such claims is limited.

When it comes to fearmongering in turfgrass, I’m not sure there is a bigger one than bicarbonate (HCO3-). One often hears of supposed problems associated with bicarbonate. I’m still waiting to see a soil or turfgrass problem associated with this ubiquitous anion.

This concerns the use of saturated paste (water) or dilute water extractants for assessing soil nutrient content, and specifically if data from those tests are a good way to decide if an element should be supplied as fertilizer.

I measured soil moisture and surface hardness on three fairways, approaches, and greens at a golf course in Thailand in September 2014. The fairways and approaches at this site are seashore paspalum on a sandcap.